Widjaja W, Vale C. COUNTEREXAMPLES: CHALLENGES FACED BY ELEMENTARY STUDENTS WHEN TESTING A CONJECTURE ABOUT THE RELATIONSHIP BETWEEN PERIMETER AND AREA. j. math. educ. [Internet]. 2021 Sep. 1 [cited 2025 Apr. 19];12(3):487-506. Available from: http://jme.ejournal.unsri.ac.id/index.php/jme/article/view/3648